Gyro decaging mechanism



Nov- 22, 19 M. H. STILL ETAL GYRO DECAGING MECHANISM 2 Sheets-Sheet 1 Filed June 29, 1959 Nov. 22, 19 M. H. STILL ETAL (mo DECAGING mzcmmrsu Filed June 29, 1959 2 Sheets-Sheet 2 United States Patent GYRO DECAGING MECHANISM Michael Holland Still, Weyhridge, Trevor Wooderson, 91d Waking, and Arthur Charles Fry, Send, England, assignors to Vickers-Armstrongs (Aircraft) Limited, London, England Filed June 29, 1959, Ser. No. 823,445

Claims riority, application Great Britain July 2, 1958 6 Claims. (Cl. 745.12)

This invention has reference to gycroscopes or gyroscope assemblies whereof the rotors are provided with turbine means by which they may be run up to operating speed by application thereto of pressure fluid jets, the pressure fluid being supplied froma source under compression, or by combustion of a cartridge charge. More particularly, the invention is concerned with mechanism in apparatus of the class afore-described for decaging the gycroscopes automatically on completion of the runningup operation, after the pressure fluid reaction with the turbine has ceased, and its object is to provide improved mechanism for this purpose.

Gyroscope apparatus of the aforesaid class in accordance with the invention includes a pressure fluid distributing unit which is movable between a position in which it holds the gimbal assembly of the gyroscope or gyroscopes positively against displacement and a position in which said assembly is freed for rotation, said unit carrying a pressure fluid supply, means on said unit for directing jets of pressure fluid from said supply on to the rotor or rotors in the caged condition, means for retaining the unit in the caging position, and means responsive to the efliuxion of the pressure fluid supply for rendering said retaining means inoperative and for moving the unit to the uncaged position.

The distributing unit may be mounted so as to he slidable in relation to the gyroscope gimbal assembly between the caged and uncaged positions.

The pressure fluid supply may consist of a container for a quantity of the pressure fluid (which may be air or other gas) in compression, or for a gas generator cartridge.

A preferred embodiment of the invention, as applied to gyroscope apparatus comprising two rotors each mounted in its individual gimbal assembly, arranged for rotation about two axes disposed at right angles to each other, is illustrated in the accompanying drawings, reference to which will be made in the following description. Said drawings depict in Fig. 1 an end elevation (partly broken away) of the apparatus, in Fig. 2 a plan, in Fig. 3 a section on the line AB of Fig. 1, showing the parts in the caged position, and in Fig. 4 a sectional view similar to Fig. 3 but showing the parts in the uncaged position.

The apparatus comprises a basal frame on which the two rotor-cum-gimbal assemblies are mounted. Each such assembly consists of a rotor 11 mounted in an inner gimbal 12 which is itself supported in an outer gimbal 13. The rotor axes are indicated respectively by the lines C-D and E-F in Fig. 1. Each rotor 11 is provided with a pair of turbine blade rings 111 which, in the caged position, are located in operative relationship to jet nozzles 14, 14 of which two pairs are provided in a block 15 which constitutes the principal-portion of the distributing unit. Said nozzles 14 are each connected by a duct 16 with the head of gas chamber 17 communicating with a canister 18 fixed upon the block 15 by a screw-thread connection 181 (Figs. 3 and 4). The canister 18 houses Patented Nov. 22, 1960 a gas generator cartridge 19 which may be ignited electrically by way of the leads 2%, the cartridge 19 being retained by a screw-threaded breech block 21.

The block 15, together with the nozzles 14 and the canister 18 carried thereby, is slidable in the bore 101 of the frame 10 between the position shown in Figs. 1, 2 and 3, and that shown by Fig. 4. In the former position the gimbals 13 are locked by their location between the opposing faces 151 of the limbs 152 of the block 15, and in which the gimbals 12 are locked by the abutment of the faces 121 thereof against the sides of said limbs 152. In the position of Fig. 4 the limbs 152 of the block 15 have been translated out of engagement with the gimbals 12, 13 and the latter are released for operational movement in response to deflections of the apparatus about the rotor axes.

Rigidly secured in the block 15 of the distributing unit is a cylindrical member 22 which extends through the chamber 17 into the base of the canister 18, the innerend of said member 22 being formed with a perforated wall 221 which serves as a filter and allows gases to pass from the canister through the chamber 17 and the ducts 16 to the jet nozzles 14. The member 22 is formed with a central bore 222 in which is slidably mounted a sleeve 23 in relation to which the block 15 moves when the gyroscopes are uncaged. A fluid pressure seal ring 24 is provided between said cylindrical member 22 and said sleeve 23, said ring 24 being housed in an annular groove in the inner wall of said member 22.

The sleeve 23 is formed with aligned transverse bores 231 each of which accommodates steel balls 25 which in the caged position protrudes by approximately one third of its radius at the outer end of the cylindrical member. The said balls 25 are prevented from moving inwards by means of a piston member 26 which is in turn slidable axially within said sleeve 23. The said balls 25 thus provide a one-way lock between said sleeve 23 and said member 22. The piston 26 is provided with a neck 261 of reduced diameter which in the caged position is displaced from the zone of the steel balls 25, but on the piston 26 being moved outwardly in the sleeve 23, the said neck 261 is brought opposite the said balls 25 allowing them to move inwardly and permit relative movement between the sleeve 23 and cylindrical member 22. The outer end of the bore through the sleeve is of reduced diameter at 232 and is vented to the atmosphere by the port 233, and between said port 233 and said piston 26 the sleeve 23 is provided with a valve seating 234 which is arranged to be engaged by the outer conical end of the piston 26, to seal said port 233 from the sleeve bore when the steel balls 25 are freed to move inwardly as aforesaid.

The outer end of the sleeve 23 is arranged to engage with an adjusting screw 27 mounted in a bridge piece 28 fixed to the frame 10, so that when the sleeve 23 is locked as aforesaid to said cylindrical member 22, said screw 27 also serves to determine the position of the distributing unit block 15 in the frame 10. The distributing unit block 15 is loaded by means of springs 29 in a direction urging it to move into the decaging position and the reaction of said springs 29 is normally balanced by said adjusting screw 27.

In operation, gas generated by the cartridge 19 passes into the chamber 17 and the pressure rises rapidly therein, the gas being conveyed through the ducts 16 to the jet nozzles 14 to run up the rotors 11. At the same time the gas pressure drives the piston 26 outwardly until its tapered end engages the valve seat 234 in the sleeve 23. This movement of the piston 26 brings the neck 261 therein into registration with the steel balls 25, so that they are free to move out of engagement with the cylindrical member 22. The block 15 and the member 22 are now mechanically free to move in relation to the sleeve 23, although the relative positioning of said sleeve 23 and member 22 will be unaltered so long as the gas pressure is maintained in the chamber 17. During this time the distributing unit block 15' and the parts carried. thereby are unable to slide on the sleeve 23 becauseof;

ber 30 is conveniently inserted between it, the piston; and' the interior of the canister 18'. Such filter member 36. maybe. dispensed with where a compressed air charge is used to run up the rotors. The distributing unit is preferably furnished with asafety device. in." the form.

of the vent 31 closed by a burstable disc.

In" an alternative embodiment the steel balls 25 which serve to lock the sleeve 23 to the cylindrical member 22,

are arranged to project into. an annular groove formed.

on the inner wall of said member.

What we claim as our invention and desire to secure by Letters Patent is:

1. Gyroscopic apparatus comprising a. rotor provided with turbine means by which said rotor can be run up to operating speed by the application. thereto of pressure fluid jets, supply means for supplying a limited amount of pressure fluid, caging means for caging rotor-support- 7 ing components of the gyroscopic apparatus including an outer sleeve mounted for sliding movement, locking. means for'locking said caging means in the caging position, said lockingmeans including a fixed inner sleeve on which the outer sleeve is slidably mounted and a captive ball arrangement, retainingmeans for retaining: said locking means in the locking position in the absence of pressure fluid and being responsive to said pressure fluid to move to a position to release said locking means, saidretaining means including a piston slidable within the inner sleeve from a first position in which the captive balls are driven into locking engagement with the outer sleeve to a second' position in which said balls are free to move out of engagement with said outer sleeve, said caging meansbeing adapted to be held in the cagingposition by a thrust applied thereto by said pressure fluid, and

biasing means for biasing the said caging means toward" an uncaging position whereby upon termination of the pressure fluid supply the caging means moves to the" uncaging' position.

2. Gyroscopic apparatus comprising a rotorprovided with turbine means by which said rotor can be run up to operating speed by the application thereto of pressurefluid jets, supply means for supplying a limited amount of pressure fluid, caging means for caging rotor supporting components of the gyroscopic apparatus, said caging means including an outer sleeve mounted for sliding movement from a first position in which said caging means occupies a caging position to a second position in which said caging means occupies an uncaging position, locking means for releasably locking said outer sleeve in the first position, said locking means comprising an inner sleeve on which saidouter sleeve is slidably mounted, a captive ball arrangement carried by said inner sleeve and a fluid-pressure responsive piston slidable within the inner sleeve from a first position which it occupies inthe absence of fluid pressure and in which the captive balls are held by it in locking engagement with the outer sleeve, to asecond position to which it moves in response to fluid pressure and in which said balls arefree zto move out of engagement with said outer sleeve, said cagin'g meansvbeing adaptedkto-beheld in the cagingposition by a thrust-supplied thereto by said. pressure fluid, and biasing; means for biasing said caging means towards the uncaging position whereby upon termination of the pressure fluid supply the caging means moves to the uncaging position 3. Gyroscopic' apparatus according to claim 1, wherein the outer sleeve is rigidly connected to a pressure fluid distributing unitwhi'ch servessimultaneously to distribute pressure fluid tothe turbine means of the rotor and to cage the rotor-supporting components.

4-. Gyroscopic apparatus according to claim 3, wherein the'p'ressure fluid supply' means: comprises. a gas: generator cartridge carried in a container communicating with and rigidly connected to the fluid: distributing unit.

5. Gyroscopic apparatus according to claim 4, wherein said biasing means: comprise tension springs connected between the cartridge container and a fixed component ofthe apparatus.

6. Apparatus'according'to claim 3, wherein the pressure fluid distributing unit is adapted to supply pressure fluid to a pair of gyroscopic rotors mounted for rotation about mutually perpendicular axes and also to cage the rotor-supporting components associated with the two rotors.v

References Cited in the file of this patent UNITED STATES'PATENTS 741,683 Leavitt Oct. 20, 1903 954,634 Jones Apr. 12; 1910 1,077,344 Hennig Nov; 4, 1913 1,185,210 Leavitt' May 30, 1916 2,415,899 Meyer et al. Feb. 18, 1947 

